Film cut-out



sept. 17, 1935.

L. J, BARWOOD FILM CUTLOUT Filed June 8, 1932 Unef-M07* [16611 J. awood L? J .v NNK..

Patented Sept. 17, 1935 UNIT-ED S `014,@1419 riiiu oUTv-oUfi Leon Joachim Barwood, Cambridga Mass. appiiatieii .ninel `s, 1932, serial No. t616,690

2/3 claims. (ci. .26d-,116)y Y P J diametrical section taken upon the line 2-2 of Fig. 1, lookingy in the direction of the arrows; Fig. 3 is aview similar to Fig. 1 of a modification; Fig. 4 is a section taken upon Athe line 4 4 of Fig. 3, looking in the direction of the arrows;

` Fig. 5 is an enlarged and exaggerated section of a further modification corresponding to the' embodiment 4shown in Figs. 1 and 2; and Fig. 6 is a section of another modioaton.

.A-lm cut-out may comprise two members 2 and 4, of conducting material, like metal, insuvlated from each other in any desired manner, rasby' means of an insulating iilrn 6 disposed between andy separating the conducting members, as illustrated in Figs.'1 to 4 and 6. The separating film 6 may, however,r be omitted and the ysurfaces of thev metal members 2 and 4 maybe covered with a suitable insulating coating 20 of an oxide of the metal instead, as illustrated in Fig. 5. The metal may, for example, be aluminum. The oxide coating 2D is shown as completely encasing the Imetal members l2 and 4 (ex'ce'pt possibly, Where theV outer surfaces of the members 2 and 4 may be engaged by suitableelectrodes) but, in practice, it is only necessary to have the insulating coatingalong the contacting inner surfaces ofthe members 2 and 4. `It will be underl stood that the oxide' coating may also be employed yin the `modification illustrated in Figs. 3, '4 andv.

The iilm 6 may be of silk or any other desired material, but it isl preferred, according tothe present invention, to employ a thin nlm ofr paper, f'such as tissue paper'. Accordingto the present invention, furthermore, the members 2,4 and 6 are held togethermechanically as a unit in novel fashion and by novel mechanical-means embodying an element or elements separate from the j conductingvmembers 2 and 4 and preferably, also, the insulating lm 6. The mechanical holding means 'comprises an annular insulating disc 8, f Figs'. 1 and 2, or two annular insulating discs Il) VandlZ, Figs. 3, 4 and 6, ory lany equivalentrnech- "anism, as will be understood, forvengagng `the v'cilin1; luctingv members 2 and 4 at their peripheries and for holding the conductingandtheinsulating members together as a unit. As it is preferred to have the conductingl members 2` and'f4,'-"ar`1'd also, if desired, the insulating member" 36, circular or ldisc-shape inform, the 4rneinbers* 8',` LI l) "and"` 'l2 are shown as ring-shaped or-annular; -The-nei- 5 perse; I 0 l"and i2 jinay be of4v any' desirediin'sulating material, `but suflicently-stiif td'holdf'the parts (together. A suitable bre hasbeenfiound very Asatisfactory in practice. In this ma the conducting discs f2 and l'and the ng 10 lm are held together asaunit in the A o` ning f' y in the annular bre disc 8, oir-inthe opening" or openings of the annular 'fibre 'discsf Iandf 12.-

" 'Accordingto ythe'form f the invention shown in Figs. l vand 2,`the'"discs 2 and 4 vand tl'eiiln 15 6"'are held ltogether as a `unit merely by 'the i" peripheries of the discs 2 and 4 frictionally-'engagingv the wall of the opening in the' annular disc k8.y To this en d, the vsaid Wall of the opening vinthe annular dise 6 may be siig-huy torus-shaped 26 or concave, but thisis not essential, for theparts f Will be held together very' elfectively with any vshaped opening in4 the annular v'disc gf provided that`r theddiameter ofthe discs `2 fand l 4 is slightly greater 'than 'the diameter-bf Ithe"openingl'in the 25 annular disc 8.A The' peripheral edges A'of the said torus-'shaped or concave' walls provide projections between which ine'disjcs zand -4 are heid. Though 'the"partsar'e thus effectively held to'getherfrictional'ly'asfa unit, it is nevertheless possible quick- 30 "ly'ht'o detach the parts 2,' 4 and 6 'from the annular f f disc 3v and'a'squickly to'reassemble `'the same-for other like parts, if desired. /All thatiis necessary is to slide the" annular disk -8 :frictionally over the jsaid peripheries Yof Vthel'di'scsV Zvand 4." 1 -f "According tothe modificati'onof Figs. 4 and,6, however, theannula'r discs I0 and l2, ofthe Isame or similar construction,"are each providedf'wth 'an' annular recess i i 4 lsurrounding theopeningfin rthe' corresponding' annular'dis'cs I0 and `I2?, and 40 y getherf's shown more yparticulariv infFigs". Lland `6,`in the recesses I4.v The `annular discs 'I0 and I2 are rigidly secured together, with the conducting dises` 2 and 4 in assembled position, infany 45 desired manner, as by means of rivets I6. 'Thez rivets Iifneed not necessarily be separate members, as illustrated in Figs. 3 and 4', butthe'y may be formed integal with, or pressed out froiirfone of the' 'discs lo and laas the disc lo; aiiifem- 5o bedded in the otherdisc, as the disc 122;'ftol'iold lessdiameter than, the diameter of :they annular if 'ry '";.i i

discs I and l2, so that the rivets I6, or the corresponding pressed-out rivets (not shown) may extend through the insulating film 6, as illustrated in Figs. 4 and 6.

It will be noted that the use of rivets is really not necessary, because the friction method of holding the parts together, illustrated more particularly in Figs. 1 and 2, is found to be very effective, in practice.

It is ypreferred to have the conducting discs 2 and 4 centrally-bowed-out, with the bowed-out portions disposed opposite to, and out of contact with, each other, and the peripheral non-bowedout portions adjacent to each other, as clearly shown in both Figs. 2, 4, 5 and 6. According to this construction, therefore, the insulating film contacts with the non-bowed-out peripheral portions, but is out of contact with the bowed-out portions. An air chamber I8 is thus provided between the insulating disc 5 and each centrallybowed-out portion of the disc 2 and 4.

A lm cut-out made in accordance with the present invention has a remarkably uniform break-down voltage.

It will be understood that the invention is not limited to the exact embodiments thereof that are herein illustrated and described, but that further modifications may be made without departing jj from the spirit and scope of the invention as 30 defined in the appended claims.

What is claimed is:

1. A film cut-out comprising two conducting members, an insulating film disposed between and separating the conducting members, and insulating means for frictionally engaging the peripheries of the conducting members to mechanically hold the conducting members, the insulating iilm and the insulating means together as a unit, the insulating means being slidable frictionally over the said peripheries to permit quick frictional detachment of the insulating means and the conu ducting members and the insulating film.

2. A nlm cut-out comprising two conducting members, an insulating film disposed between and separating the conducting members, and means separate from the conducting members for frictionally engaging the peripheries of the conducting members to mechanically hold the conducting members, the insulating lm and the means together as a unit, the means beingslidable frictionally over the said peripheries to permit quick frictional detachment of the means and the conducting members andthe insulating film.

3. A lm cut-out comprising two conducting members, an insulating film disposed between and separating the conducting members, and means comprising a concave wall engaging the conducting members at their peripheries for mechanically holding the conducting members, the insulating film and the means together as a unit.

4. A iilm cut-out comprising two conducting members, an insulating film disposed between and separating the conducting members, and means having an opening in which the conducting and the insulating iilm are disposed, the wall of the opening being torus-shaped to mechanically hold the conducting members and the insulating film together as a unit in the opening.

5. A iilm cut-out comprising two insulated conducting members, and a member having an opening in which the conducting members are disposed, the wall of the opening being concavek to mechanically hold the conducting members together as a unit in the opening.

6. A lm cut-outrrcomprising two insulated conuaonifios ducting discs, and a member having an opening in which the conducting discs are disposed, the wall of the opening being slightly smaller than the diameter of the discs and being peripherally engaged by the discs to frictionally hold the conducting discs together as a unit in the opening.

7. A film cut-out comprising two conducting members, an insulating film disposed between and separating the conducting members, two similar members each having a similar opening, and means for mechanically holding the similar members together with the openings opposed to each other and with the conducting members and the insulating film disposed as a unit between the similar members in the openings,

8. A film cut-out comprising two insulated bowed-out conducting members disposed adjacent to each other with the bowed-out portions disposed opposite to and out of contact with each other, and means for frictionally engaging the peripheries of the conducting members to mechanically hold the conducting members together as a unit.

9. A lm cut-out comprising two centrallyripheral portions, and means for frictionally env gaging the peripheral edges of the discs for holding the conducting discs and the insulating 'iilm together as a unit.

10. A film out-out comprising two centrallybowed-out conducting discs disposed adjacent to each other with the bowed-out portions disposed opposite to and out of contact with each other, an insulating film disposed between the conducting discs and separating the non-bowed--outperipheral portions, and annular means having a torus-shaped wall of slightly smaller diameter than the diameter of the discs for engaging the discs at their peripheries for holding the discs and the insulating nlm together as a unit.

1l. A film cut-out comprising two centrallybowed-out metal discs disposed adjacent to each other with their bowed-out portions disposed out of contact with each other, an insulating paper film disposed between the metal discs and separating the non-bowed-out peripheral portions, and an annular fibre disc having a torus-shaped wall of slightly smaller diameter than the diameter of the metal discs for engaging the peripheral edges of the metal discs for holdingthe discs and the insulating film together as a unit.

12. A film cut-out comprising two conducting members, an insulating film disposed between and separating thev conducting members, and insulating means for frictionally holding the conducting members and the insulating film together as a unit, the insulating means being slidable frictionally with respect to the conducting members and the insulating film to permit quick frictional detachment of the insulating means, and the conducting members and the insulating lm.

13. A film cut-out comprising two conducting discs, an insulating film disposed between and separating the conducting discs, and means having an opening in which the conducting discs and the insulating film are disposed, the wall of the opening being concave and slightly smaller than the diameters of the discs and being peripherally engaged by the discs to frictionally hold the conducting discs and the insulating film together as a unit in the opening.

14. A film cut-out comprising two insulated centrally-bowed-out conducting discs disposed adjacent to each other with the bowed-out portions disposed opposite to and out of contact with each other, and annular means having a torus-shaped wall of slightly smaller diameter than the diameter of the discs for engaging the discs at their peripheries for frictionally holding the discs and the insulating film together as a unit.

15. A lm cut-out -comprising two insulated conducting members, and means for frictionally engaging the peripheresof the conducting members to mechanically hold the members together as a, unit, the said means being slidable frictionally over the said peripheries to permit quick frictional detachment of the said means and the conducting members.

16. A nlm cut-out comprising two conducting members in contact with each other and each having an insulating coating at the contacting surfaces, and means frictionally engaging the periperies of the conducting members to hold the members together as a unit, the said means being slidable frictionally over the said peripheries to permit quick frictional detachment of the said means and the conducting members.

17. A lm cut-out comprising two insulated conducting members, and means having an opening in which the conducting members are clisposed, the walls of the opening engaging the conducting members at their peripheries for frictionally holding the conducting members and said means together as a unit, said walls of the opening being slidable frictionally over the said peripheries to permit quick frictional detachment of said means and the conducting members.

18. A lm cut-out comprising two conducting members, an insulating lm disposed between and separating the conducting members, and means comprising a wall engaging the conducting members at their peripheries for mechanically holding the conducting members and the means together as a unit, the wall being provided with projections between which the conducting meinbers are held.

19. A lm cut-out comprising twoinsulated conducting members, and means having an opening in which the conducting members are disposed, the wall of the opening being provided with projections between which the conducting members and the means are held together as a unit.

20. A lm cut-out comprising two insulated conducting discs, and means having an opening in which the conducting discs are disposed, the

wall of the opening being slightly smaller than the diameter of the discs and being peripherally engaged by the discs to frictionally hold the conducting discs together as a unit in the opening, the wall being provided with projections between which the conducting members are held.

21. A lm cut-out comprising two insulated conducting members, and means having an opening in which the conducting members are disposed, the walls of the opening engaging the conducting members at their peripheries for frictionally holding the conducting members and said means together as a unit, said walls of the opening being slidable frictionally over the said peripheries to permit quick frictional detachment of said means and the conducting members, and said walls of the opening being provided with projections between which the conducting members are held.

22. A film cut-out comprising two conducting members, an insulating lm disposed between and separating the conducting members, and insulating means having an opening in which the conducting members and the insulating film are disposed, the walls of the opening engaging the conducting members at their peripheries for frictionally holding the conducting members, the insulating film and said means together as a unit, said walls of the opening being slidable frictionally over the said peripheries to permit quick frictional detachment of said means and the conducting members, and said walls of the opening being provided with projections between which the conducting members are held.

23. A lm cut-out comprising two insulated conducting members, and means for frictionally engaging the peripheries of the conducting members to mechanically hold the conducting members together as a unit, the said means being slidable frictionally over the said peripheries to permit quick frictional detachment of the said means and the conducting members, and the said means having projections between which the conducting members are held.

LEON J. BARWOOD. 

